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涓轰簡閬垮厤姝婚攣鐨勫彂鐢燂紝JDK 涓熀鏈兘鏄彲閲嶅叆閿併€?/p>
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- 娴嬭瘯 synchronized 鍔犻攣 鍙噸鍏ユ€?/li>
package constxiong.concurrency.a019;/** * 娴嬭瘯 synchronized 鍔犻攣 鍙噸鍏ユ€? * @author ConstXiong * @date 2019-09-20 15:55:27 */public class TestSynchronizedReentrant {public static void main(String[] args) {new Thread(new SynchronizedReentrant()).start();}}class SynchronizedReentrant implements Runnable {private final Object obj = new Object();/** * 鏂规硶1锛岃皟鐢ㄦ柟娉? */public void method1() {synchronized (obj) {System.out.println(Thread.currentThread().getName() + " method1()");method2();}}/** * 鏂规硶2锛屾墦鍗板墠鑾峰彇 obj 閿? * 濡傛灉鍚屼竴绾跨▼锛岄攣涓嶅彲閲嶅叆鐨勮瘽锛宮ethod2 闇€瑕佺瓑寰?method1 閲婃斁 obj 閿? */public void method2() {synchronized (obj) {System.out.println(Thread.currentThread().getName() + " method2()");}}@Overridepublic void run() {//绾跨▼鍚姩 鎵ц鏂规硶1method1();}}鎵撳嵃缁撴灉锛?/p>
Thread-0 method1()Thread-0 method2()- 娴嬭瘯 ReentrantLock 鐨勫彲閲嶅叆鎬?/li>
package constxiong.concurrency.a019;import java.util.concurrent.locks.Lock;import java.util.concurrent.locks.ReentrantLock;/** * 娴嬭瘯 ReentrantLock 鐨勫彲閲嶅叆鎬? * @author ConstXiong * @date 2019-09-20 16:24:52 */public class TestLockReentrant {public static void main(String[] args) {new Thread(new LockReentrant()).start();}}class LockReentrant implements Runnable {private final Lock lock = new ReentrantLock();/** * 鏂规硶1锛岃皟鐢ㄦ柟娉? */public void method1() {lock.lock();try {System.out.println(Thread.currentThread().getName() + " method1()");method2();} finally {lock.unlock();}}/** * 鏂规硶2锛屾墦鍗板墠鑾峰彇 obj 閿? * 濡傛灉鍚屼竴绾跨▼锛岄攣涓嶅彲閲嶅叆鐨勮瘽锛宮ethod2 闇€瑕佺瓑寰?method1 閲婃斁 obj 閿? */public void method2() {lock.lock();try {System.out.println(Thread.currentThread().getName() + " method2()");} finally {lock.unlock();}}@Overridepublic void run() {//绾跨▼鍚姩 鎵ц鏂规硶1method1();}}鎵撳嵃缁撴灉锛?/p>
Thread-0 method1()Thread-0 method2()娴嬭瘯涓嶅彲閲嶅叆閿?/strong>
鎴戝湪 JDK 涓病鎵惧埌鍙噸鍏ラ攣锛屾墍浠ヨ€冭檻鑷繁瀹炵幇涓€涓嬨€備袱绉嶆柟寮忥細閫氳繃 synchronized wait notify 瀹炵幇锛涢€氳繃 CAS + 鑷棆鏂瑰紡瀹炵幇
1锛?synchronized wait notify 鏂瑰紡瀹炵幇
package constxiong.concurrency.a019;/** * 涓嶅彲閲嶅叆閿侊紝閫氳繃 synchronized wait notify 瀹炵幇 * @author ConstXiong * @date 2019-09-20 16:53:34 */public class NonReentrantLockByWait {//鏄惁琚攣private volatile boolean locked = false;//鍔犻攣public synchronized void lock() {//褰撴煇涓嚎绋嬭幏鍙栭攣鎴愬姛锛屽叾浠栫嚎绋嬭繘鍏ョ瓑寰呯姸鎬?while (locked) {try {wait();} catch (InterruptedException e) {e.printStackTrace();}}//鍔犻攣鎴愬姛锛宭ocked 璁剧疆涓?truelocked = true;}//閲婃斁閿?public synchronized void unlock() {locked = false;notify();}}2锛?nbsp;閫氳繃 CAS + 鑷棆 鏂瑰紡瀹炵幇
package constxiong.concurrency.a019;import java.util.concurrent.atomic.AtomicReference;/** * 涓嶅彲閲嶅叆閿侊紝閫氳繃 CAS + 鑷棆 瀹炵幇 * @author ConstXiong * @date 2019-09-20 16:53:34 */public class NonReentrantLockByCAS {private AtomicReference<Thread> lockedThread = new AtomicReference<Thread>();public void lock() {Thread t = Thread.currentThread();//褰?lockedThread 鎸佹湁寮曠敤鍙橀噺涓?null 鏃讹紝璁剧疆 lockedThread 鎸佹湁寮曠敤涓?褰撳墠绾跨▼鍙橀噺while (!lockedThread.compareAndSet(null, t)) {//鑷棆锛岀┖寰幆锛岀瓑鍒伴攣琚噴鏀?}}public void unlock() {//濡傛灉鏄湰绾跨▼閿佸畾鐨勶紝鍙互鎴愬姛閲婃斁閿?lockedThread.compareAndSet(Thread.currentThread(), null);}}娴嬭瘯绫?/p>
package constxiong.concurrency.a019;/** * 娴嬭瘯涓嶅彲閲嶅叆閿? * @author ConstXiong * @date 2019-09-20 18:08:55 */public class TestLockNonReentrant{public static void main(String[] args) {new Thread(new LockNonReentrant()).start();}}class LockNonReentrant implements Runnable {//private final NonReentrantLockByWait lock = new NonReentrantLockByWait();private final NonReentrantLockByCAS lock = new NonReentrantLockByCAS();/** * 鏂规硶1锛岃皟鐢ㄦ柟娉? */public void method1() {lock.lock();try {System.out.println(Thread.currentThread().getName() + " method1()");method2();} finally {lock.unlock();}}/** * 鏂规硶2锛屾墦鍗板墠鑾峰彇 obj 閿? * 濡傛灉鍚屼竴绾跨▼锛岄攣涓嶅彲閲嶅叆鐨勮瘽锛宮ethod2 闇€瑕佺瓑寰?method1 閲婃斁 obj 閿? */public void method2() {lock.lock();try {System.out.println(Thread.currentThread().getName() + " method2()");} finally {lock.unlock();}}@Overridepublic void run() {//绾跨▼鍚姩 鎵ц鏂规硶1method1();}}娴嬭瘯缁撴灉锛岄兘鏄湪 method1锛岃皟鐢?method2 鐨勬椂鍊欙紝瀵艰嚧浜嗘閿侊紝绾跨▼涓€鐩寸瓑寰呮垨鑰呰嚜鏃嬩笅鍘汇€?/p>
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